1222020161 has 2 divisors, whose sum is σ = 1222020162. Its totient is φ = 1222020160.

The previous prime is 1222020157. The next prime is 1222020179. The reversal of 1222020161 is 1610202221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1043290000 + 178730161 = 32300^2 + 13369^2 .

It is an emirp because it is prime and its reverse (1610202221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1222020161 - 2² = 1222020157 is a prime.

It is not a weakly prime, because it can be changed into another prime (1222020181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 611010080 + 611010081.

It is an arithmetic number, because the mean of its divisors is an integer number (611010081).

Almost surely, 2^1222020161 is an apocalyptic number.

It is an amenable number.

1222020161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1222020161 is an equidigital number, since it uses as much as digits as its factorization.

1222020161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1222020161 is about 34957.4049523130. The cubic root of 1222020161 is about 1069.1191869053.

Adding to 1222020161 its reverse (1610202221), we get a palindrome (2832222382).

The spelling of 1222020161 in words is "one billion, two hundred twenty-two million, twenty thousand, one hundred sixty-one".